package com.mh.controltool2.servlet;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public interface HandlerInterceptor {

//    /**
//     * Intercept the execution of a handler. Called after HandlerMapping determined
//     * an appropriate handler object, but before HandlerAdapter invokes the handler.
//     * <p>DispatcherServlet processes a handler in an execution chain, consisting
//     * of any number of interceptors, with the handler itself at the end.
//     * With this method, each interceptor can decide to abort the execution chain,
//     * typically sending a HTTP error or writing a custom response.
//     * <p><strong>Note:</strong> special considerations apply for asynchronous
//     * request processing. For more details see
//     * {@link org.springframework.web.servlet.AsyncHandlerInterceptor}.
//     * <p>The default implementation returns {@code true}.
//     * @param request current HTTP request
//     * @param response current HTTP response
//     * @param handler chosen handler to execute, for type and/or instance evaluation
//     * @return {@code true} if the execution chain should proceed with the
//     * next interceptor or the handler itself. Else, DispatcherServlet assumes
//     * that this interceptor has already dealt with the response itself.
//     * @throws Exception in case of errors
//     */
    default boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        return true;
    }

//    /**
//     * Intercept the execution of a handler. Called after HandlerAdapter actually
//     * invoked the handler, but before the DispatcherServlet renders the view.
//     * Can expose additional model objects to the view via the given ModelAndView.
//     * <p>DispatcherServlet processes a handler in an execution chain, consisting
//     * of any number of interceptors, with the handler itself at the end.
//     * With this method, each interceptor can post-process an execution,
//     * getting applied in inverse order of the execution chain.
//     * <p><strong>Note:</strong> special considerations apply for asynchronous
//     * request processing. For more details see
//     * {@link org.springframework.web.servlet.AsyncHandlerInterceptor}.
//     * <p>The default implementation is empty.
//     * @param request current HTTP request
//     * @param response current HTTP response
//     * @param handler handler (or {@link HandlerMethod}) that started asynchronous
//     * execution, for type and/or instance examination
//     * @param modelAndView the {@code ModelAndView} that the handler returned
//     * (can also be {@code null})
//     * @throws Exception in case of errors
//     */
//    default void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception { }

//    /**
//     * Callback after completion of request processing, that is, after rendering
//     * the view. Will be called on any outcome of handler execution, thus allows
//     * for proper resource cleanup.
//     * <p>Note: Will only be called if this interceptor's {@code preHandle}
//     * method has successfully completed and returned {@code true}!
//     * <p>As with the {@code postHandle} method, the method will be invoked on each
//     * interceptor in the chain in reverse order, so the first interceptor will be
//     * the last to be invoked.
//     * <p><strong>Note:</strong> special considerations apply for asynchronous
//     * request processing. For more details see
//     * {@link org.springframework.web.servlet.AsyncHandlerInterceptor}.
//     * <p>The default implementation is empty.
//     * @param request current HTTP request
//     * @param response current HTTP response
//     * @param handler handler (or {@link HandlerMethod}) that started asynchronous
//     * execution, for type and/or instance examination
//     * @param ex exception thrown on handler execution, if any
//     * @throws Exception in case of errors
//     */
    default void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception { }


}
